Nara Cuisine Kakinoha Zushi Persimmon Leaf Sushi

Ingredients

• 2 mackerel fillets (saba), skin-on, pin-boned, for shime saba curing
• 60 g fine sea salt, for curing the mackerel
• 200 ml rice vinegar, for curing the mackerel
• 400 g Japanese short-grain rice, cooked as sushi rice
• 60 ml rice vinegar, for seasoning the cooked rice
• 20 g caster sugar, for seasoning the cooked rice
• 8 g fine sea salt, for seasoning the cooked rice
• 12 fresh persimmon leaves (kakinoha), young tender leaves (June–July) or mature summer leaves (August–September); wiped clean, stems trimmed

Method

1. 1
   Salt the mackerel fillets generously on both sides with the fine sea salt. Lay them on a rack set over a tray and refrigerate uncovered for 2–3 hours. The surface of the flesh will appear visibly drier and the fillets will have shed liquid. Rinse briefly under cold water and pat dry.
2. 2
   Submerge the salted fillets in the rice vinegar for a further 1–2 hours. The flesh will turn opaque from the surface inward; it should be fully white-opaque to the centre when sliced across at the thickest point. This is shime saba. Remove, pat dry, peel away the thin iridescent skin, and slice on a gentle diagonal into pieces approximately 1 cm thick. The fish must be thoroughly cured before wrapping — inadequately cured fish will spoil during the pressing period.
3. 3
   Season the hot cooked rice with the combined rice vinegar, sugar, and salt, folding with a flat spatula while fanning to cool. The rice should be glossy, each grain distinct but cohesive, and hold its shape when pressed in the palm.
4. 4
   Lay each persimmon leaf flat with its shiny surface facing upward. Place a compact oval of seasoned rice — approximately 35 g — at the centre of the leaf. Lay one slice of shime saba on top of the rice, fish side down against the rice. Fold the leaf firmly around the package, bringing the sides in first, then folding the tip over. The leaf's shiny surface must face inward, directly against the rice and fish; this is the surface through which the leaf's tannins and antimicrobial compounds act.
5. 5
   Arrange the wrapped packages in a single layer, seam-side down, in a flat-bottomed container or on a pressing board. Lay a second board or flat tray directly on top and apply even weight — a filled 2-litre container or equivalent. This is the step on which the dish lives or dies: insufficient or uneven pressure will produce rice that is loose and poorly integrated rather than the characteristic dense, cohesive mass; no substitution for time or weight is possible. Press at cool room temperature or under refrigeration for a minimum of 8 hours and up to 24 hours.
6. 6
   Serve the packages still wrapped. At the table, the diner unfolds the leaf to reveal the sushi — the leaf-wrapped presentation is integral to the aesthetic. The rice surface in contact with the leaf will carry a faint earthy, slightly bitter tannic note. The packages may be consumed up to 24 hours after pressing.